Instruments, such as endoscopes, are inserted through a person's mouth into the human body, in medical procedures. To prevent the patient from biting into the instrument, a bite block is used which is generally a plastic tube which is positioned in the patient's open mouth. The instrument is then inserted through the bite block opening into the stomach or other areas.
Having a flexible rod-like instrument inserted through the mouth, on through the throat into the alimentary canal is an unnatural and unpleasant sensation to the human body, and the body struggles, voluntarily and involuntarily, to eject or destroy the instrument, particularly when the person is partially sedated. The tongue attempts to push both the instrument and the bite block which is protecting the instrument out of the mouth; the teeth bite together to attempt to bite through. The lips also work to aid in the attempted expulsion and destruction. The function of the bite block is to oppose the body's actions and to protect the patient and instrument, and to permit the physician to insert the instrument with a minimum of trouble, and to carry out the medical procedure.
Prior art bite blocks, while in place in the mouth, generally work as intended but very often the struggling patient is successful in displacing them, particularly by vigorously working the tongue so as to push the bite block out of the mouth, even while the teeth are working to bite into the block and instrument. The teeth are then free to bite into the instrument. The mouth often assists in this ejection of the bite block by opening and closing about the bite block.
With persons who are particularly strong, the problem is even greater because of such strength.